This section provides background information related to the present disclosure which is not necessarily prior art.
Electrical connectors are used in many environments wherein they are exposed to a variety of damaging materials that must be kept out of the electrical connectors for them to continue to function as designed. In a typical electrical connection a male portion having one or more electrical pins is plugged into a female portion to form the electrical connection. Sealing an electrical connection often refers to sealing this portion of the connection the male female interface, also known as the connector cavity. The connector seal in this portion can be unreliable or leak especially if the mating connector is unplugged or during servicing of the parts when contaminates can enter the connector cavity. Another issue in the connector cavity is that it is difficult to seal the wires of the female portion against moisture and water entering via capillary action within the wire. Another “cavity” found in an electrical connector is known in the art as an electronics cavity which is typically adjacent the connector cavity. One needs to seal this cavity also, especially in electrical connections that do not have a seal in the connector cavity. The electronics cavity is also important to seal for electrical connections wherein it is desirable to present an unsealed connector as when the connector presented has only the male portion. In the environment of vehicles preferably both the connector cavity and the electronics cavity of electrical connectors are sealed against intrusion by moisture, water, salt spray, dirt, dust, engine oils, engine transmission fluid, and other engine liquids. Many electrical connectors have been designed with physical features built in to block intrusion of outside materials into the electrical connector. Some of these connectors involve using a gasket to seal the connector; however these tend to be expensive, complicated and often take up too much space in the connector.
In addition, to the physical design of the electrical connector itself various sealants have been developed in an attempt to prevent damage to the electrical connections, components found in the connectors, and electronics cavities. The sealants used are known as form in place (FIP) sealants because they are applied to a location and can then be formed to fill gaps between parts. The sealants used include: epoxy type sealants, silicone based UV curable sealants, polyacrylic sealants and polyurethane sealants. Many factors influence the selection of the sealant including its ability to resist attack by the materials it is expected to be exposed to and the conditions under which it is expected to function. These conditions can include temperature extremes, salt exposure, exposure to corrosive fluids and other factors. In the past epoxy type sealants have been used for sealing electrical connectors of vehicles. One drawback with epoxy type sealants is that they often require a thermal cure process and/or long cure times. Low temperature such as room temperature cures do not usually produce a robust seal. Another problem with epoxy type sealants is that they may be weakened by any soldering process at the pins or terminals located in the electrical connector. Their slow cure cycle time makes them less than ideal for high-volume production lines. There is also the issue of thermal expansion of air trapped in the connector cavity when using high temperature cure of epoxy sealants. During the high temperatures the expanding trapped air escapes through the epoxy before it can cure causing bubbles and leak paths in the epoxy. Silicone based UV curable materials can be used to seal terminals without the long cure times needed for epoxy type sealants; however they are not compatible with certain engine fluids such as transmission fluids.
It is desirable to provide an electrical connector sealing method that can be used to successfully seal electrical connectors and in particular the electronic cavity of an electrical connector in a manner that can be adapted to a wide variety of connector designs, rapidly modified and that can be used in high-volume in line processes.